Android 图片操作（Bitmap）

/**
	 * 将多个Bitmap合并成一个图片。
	 * 
	 * @param int 将多个图合成多少列
	 * @param Bitmap... 要合成的图片
	 * @return
	 */
public static Bitmap combineBitmaps(int columns, Bitmap... bitmaps) {
		if (columns <= 0 || bitmaps == null || bitmaps.length == 0) {
			throw new IllegalArgumentException("Wrong parameters: columns must > 0 and bitmaps.length must > 0.");
		}
		int maxWidthPerImage = 0;
		int maxHeightPerImage = 0;
		for (Bitmap b : bitmaps) {
			maxWidthPerImage = maxWidthPerImage > b.getWidth() ? maxWidthPerImage : b.getWidth();
			maxHeightPerImage = maxHeightPerImage > b.getHeight() ? maxHeightPerImage : b.getHeight();
		}
		int rows = 0;
		if (columns >= bitmaps.length) {
			rows = 1;
			columns = bitmaps.length;
		} else {
			rows = bitmaps.length % columns == 0 ? bitmaps.length / columns : bitmaps.length / columns + 1;
		}
		Bitmap newBitmap = Bitmap.createBitmap(columns * maxWidthPerImage, rows * maxHeightPerImage, Config.RGB_565);

		for (int x = 0; x < rows; x++) {
			for (int y = 0; y < columns; y++) {
				int index = x * columns + y;
				if (index >= bitmaps.length)
					break;
				newBitmap = mixtureBitmap(newBitmap, bitmaps[index], new PointF(y * maxWidthPerImage, x * maxHeightPerImage));
			}
		}
		return newBitmap;
	}
/**
	 * 将多个Bitmap合